The conventual character of
Santillana consolidated in the 17th century with the
settlement of the Dominicans there. In 1592 they had
already attempted to establish themselves in the Las
Arenas Palace, but the opposition of the collegiate
church canons forced them to settle outside the urban
centre, under the protection of the Duke of Infantado.
This is how they came to build in 1628 the Convent
of Regina Coeli,
which was occupied since the 19th century by the Clarist
nuns, and is at present the Diocesan Museum. It pertains
to the first Baroque architectural style, characterized
by classicist sobriety mainly observed outside the
building. The cloister is the best in the region of
those pertaining to the Baroque period and is
artistically the most significant element in the convent.
Around it are arranged the different attached buildings,
at present being the rooms of the museum, where one can
see from medieval and modern carvings on polychromic
wood, to works donated by American and Philipines
Indianos (rich former colonials). In the so called Sala
Negra (Black Room), there is a wonderful metal work
collection from different areas of Cantabria. The museum
has also an outstanding collection of ancient book prints
and the Diocesan Archives.

Moreover, in the second half of
the 17th century, the Baroque convent of the Dominicans
of San Ildefonso was built, surrounded by high
walls. However, at that time, Santillana was already
undergoing an economic and cultural decline from which it
emerged at the end of the 17th century thanks to the
capital coming from America. From that moment, numerous
casonas were built, which gave Santillana the look of a
Baroque village, all of which have the features of palaces
and casonas montañesas. In general, the sobriety of the
classicist models, the ostentatious Baroque coats of arms
rich in lambrequins and feathers, prevail on the outside
of the casonas. The portico, the porch, the balcony and
the solana appear in many of these coats of arms. From
this period also are the Houses of Villa and of
Bustamante, both of them with balconies in pulpit, as
well as the Houses of Cosío and Quevedo, with
magnificent coats of arms. But definitely, it is the Casona of
Los Hombrones
that presents the most monumental Baroque coat of arms
guarded by two colossal warriors. Some casonas were built
on new land, such as the House of Tagle located in the Revolgo Field.
Others are outstanding both for their architectural value
and for the pieces they keep inside, such as the Benimeji Marquis's House-palace, which has a library with
incunabula manuscripts, genealogical collections and
neo-classical paintings.